Thermal circuit closer



March '8, 19271 1,620,062 F. BOSSHART THERMAL CIRCUIT CLOSER Filed Jan.4. 1926 Attorney Patented .Mar. 8, 1927.

'UNlTED STATES FRIEDRICH BOSSI-IART, 9F OSNABROCK, NORTH DAKOTA.

TIIERMAL CIRCUIT CLOSER.

Application filed January 4, 1928.

The present invention relates to a fire alarm and aims to provide adevice which may be placed in a room for ctuating switch upon theoccurrence of a fire in the room so as to close a circuit including somesuitable alarm such as an electric bell located wherever desired.

A very important object of the invention is to provide an improvedcircuit closer actuator which comprises a cylinder having a pistonslidable therein actuated by cartridges or the like mounted in thecylinder.

Another important object of the invention is to provide anexplosiveoperated circuit closer actuator of this nature which embodiesa structure wherein the movement of the parts thereof will beautomatically set so as to prevent the actuator from doing the circuitcloser any harm.

A still further very important object of the invention is the provisionof a device of this nature which is exceedingly simple in itsconstruction. compact and convenient, strong and durable, and otherwisewell adapted to the purpose for which it is designed.

lVith the above and numerous other objects in view as will appear as thedescription proceeds, the invention resides in certain novel features ofconstruction, and in the combination and arrangement of parts as will behereinafter more fully described and claimed.

In the drawing Figure 1 is a sectional elevation of the device embodyingthe features of my invention, and

Fig. 2 is an enlarged detail sectional view showing the cartridgeshells.

Referring to the drawing in detail, it will be seen that 5 designates acircuit including a .source of electrical energy 6, a knife switch 7,and an audible alarm 8 such as an electric bell. My improved actuator isdisposed so that when placed in operation. it will close the switch 7.

Referring particularly to this improved actuator, it will be seen that 9denotes a closed cylinder preferably having a detachable head 10 at oneend. A rod 11 is slidable through an opening 12 provided in the otherend of the cylinder. A piston 13 is mounted on the inner end of the rod11 and is normally located intermediate the ends of the cylinders. Avent opening 14 is provided in the cylinder 9 ofi center thereof.

Serial No. 79,123.

A plurality of cart-ridge shells 15 are threaded into the cylinder andare provided at their outer ends with reduced necks 16. Cartridges 17are located in the shells and have fuses 18 projecting therefrom throughthe necks 16.

The outer end of the rod 11 is reduced as at 19 and a coiled spring 20is partially wound thereabout, and has its extremity fixed to thereduced portion 19 by means of a screw 21 or any other suitablefastening element. A buifer member 22 is fixed on the other end of thespring 20. This spring 20 has sufficient strength to hold the bufferelement 22 in substantial alinement with the reduced portion 19. Thebuder member 22 is located in close proximity to the movable parts ofthe knife switch 7.

The parts are located in a room or the like and should a fire take placein said room, one or more of the cartridges 17 will soon be explodedbecause of the easy inflammability of the fuses 18, which, if desired,may be led about the room in a network or the like. An explosion of oneor more of the cartridges, of course, will cause an expansion of the airin the cylinder 9 behind the piston 13, thereby driving this pistonforwardly so as to abut the buffer member 22 against the knife switch 7to close said knife switch 7, thereby closing the circuit 5 for soundingthe audible alarm 8. The spring 20 compensates for the excessive strokeof the rod 11 and piston 13 occasioned by the explosion, therebypreventing any harm being done the knife switch 7.

The piston 13 will travel freely since the air in front thereof mayescape through the vent 14, but as soon as the piston passes by thisvent, air will be compressed in the forward end of the cylinder, therebyacting as a check to stop the piston 13 and preventing it from doing anyharm to the actuator or to the circuit closer with which it may beassociated.

It is thought that the construction, advantages, and operation of thisinvention will now be clearly understood by those skilled in this artwithout a more detailed description thereof. The present embodiment ofthe invention has been disclosed in detail, merely by way of example,since in actual practice, it attains the features of advantage enumerated as desirable in the statement of the invention and. the abovedescription.

It will be apparent that changes in the de= tails of construction, andin the combination and arrangement of parts may be resorted to withoutdeparting from the spirit or scope of the invention as hereinafterclaimed or sacrificing any of its advantages.

Having thus described my invention, What I claim as new is 1. A circuitcloser actuator including an explosively operated member, a coil springpartially disposed about one end of the member and fixed thereto, and abuffer element mounted on the free extremity of the coil spring, saidspring being the sole supporting means for the buffer element.

2. A circuitcloser actuator including a cylinder, an explosivelyoperated element mounted in the cylinder, cupped shells piercingopenings in the cylinder, and provided with reduced necks at their outerends through Which fuses of cartridges mounted 20 FRIEDRICH BOSSI-IART.

